Multiroll tandem mill construction



1970 M. G. SENDZIMIR MULTIROLL TANDEM MILL CONSTRUCTION 3 Sheets-Sheet 1Filed Aug. 8, 1968 I INIVENTOR. Aim/4a G e-ozwua I addaz, 4 ma ATTORNEYSOct. 13., 1970 M. G. SENDZIMIR 3,533,262

MULTIROLL TANDEM MILL CONSTRUCTION Filed Aug. 8, 1968 3 Sheets-Sheet 2lNNENTOR MICHAEL G SENDZ/M/E BY L adda, J 5 7410 l nan ATTORNEYS Oct.13, 1970 M. e. SENDZIMIR ,2

MULTIROLL TANDEM MILL CONSTRUCTION Filed Aug. 8, 1968 :5 Sheets-Sheet 5NV E N TO R Mex/4a G San/02mm ATTO RNEYS United States Patent 01 ficePatented Oct. 13, 1970 US. Cl. 72-205 7 Claims ABSTRACT OF THEDISCLOSURE The adaptation of multiroll mills, such as the Sendzimircluster mills, to tandem operation with high intrastand tension. In atandem train of such mills, the entrance stand and the exit stand aremodified in one of several Ways to provide for more even forcedistribution and more even wear of the components. Stands between theentrance and exit stands, if any, are not modified.

BACKGROUND OF THE INVENTION The invention relates to the field ofrolling mills especially for the cold reduction of metallic strandsunder high tension in a tandem train of multiroll or cluster type millssuch as are exemplified by the well known Sendzimir mill and disclosedand claimed in the Sendzimir U.S. Pats. Nos. 2,170,732, 2,194,212,2,237,794 and others.

The Sendzimir mill makes use of small diameter work rolls backed byclusters of larger rolls, some of which may be seated in massive beams.Screwdown or roll adjustment is accomplished by eccentric mounting ofthe outermost backing rolls. Rolls of this type have heretofore beenemployed as single stand mills of either one way or reverse type ofoperation. The advantages of tandem arrangement of conventional two-highor four-high mills with tension between stands are well known; but whenit is atempted to use the Sendzimir type mills in a tandem train withhigh intra-stand tension, it is found that the load and wear on theentrance and exit stands is uneven.

SUMMARY OF THE INVENTION The use of multiroll stands in a tandem trainwith high intra-stand tension, while providing for better forcedistribution and more even wear of the mill components, is madepractical by making the entrance and exit stands unsymmetrical withrespect to the vertical and in a mutually opposite sense so as to opposethe high intra-stand tension. The unsymmetry of the entrance and exitstands may be achieved in several Ways: the backing roll clusters on theentrance and exit stands may be inclined toward each other (away fromthe pay-off reel and coiler respectively); the backing structures on theentrance and exit stands may be made more robust on the mutually opposedsides thereof (the sides remote from the payoff reel and coilerrespectively), or if the mill stands are of a construction such asdescribed and claimed in Sendzimir US. Pat. No. 3,318,130 wherein theworking rolls are located in rotating jugs and can therefore bedisplaced from the centerline of the stand, the desired result may beachieved by displacing the work rolls of the entrance and exit standstoward the pay-off reel and coiler respectively. It will be understoodthat any stands which may be provided by the entrance and exit standsconventional.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a somewhat diagrammaticelevational view of a tandem train of four mills illustrating oneembodiment of the invention.

FIG. 2 is a view similar to FIG. 1 illustrating a second embodiment ofthe invention; and

FIG. 3 is a view similar to FIGS. 1 and 2 and illustrating a thirdembodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS While the drawings show in eachcase a tandem train of four mills comprising an entrance mill, twointermediate mills and an exit mill, it is to be understood that theinvention is applicable to a two-mill train comprising an entrance milland an exit mill only as well as to a tandem train comprising one ormore intermediate mills. It should also be understood that theintermediate mills, if any, may be of standard construction and thus besymmetrical about the vertical.

Referring more particularly now to FIG. 1, there is shown a tandem traincomprising an entrance mill 10, two intermediate mills 11, and an exitmill 12. The strip 13 enters the mill 10 from a pay-off reel 14 andpasses from the exit mill 12 to a coiler 15. It will be observed in thedrawing that mills 11 are symmetrical about the vertical.

The entrance mill 10 is modified in that the upper and lower clustersindicated generally by the numerals 16 and 17 are inclined as indicatedby the lines 18 and 19 in a direction away from the pay off reel.Similarly, the backing roll clusters 20 and 21 of the exit mill areinclined as indicated by the lines 22 and 23 away from the coiler 15.The amount of inclination mentioned above is determined by what isrequired to offset the tensions of the pay-off reel and the coiler. It.will be within the skill of the competent engineer to determine theoptimum inclination. As a matter of general practice, the angle of thelines 18, 19, 22 and 23 (FIG. 1) will be on the order of 4 to 12.

In FIG. 2 there is shown a modification of the invention wherein thesame result is accomplished in a different Way. The several mills arehere indicated by the reference numerals 10a, 11a and 12a. Again theintermediate mills 11a are symmetrical about the vertical and theentrance and exit mills are modified. The modification in this instanceinstead of an inclination of the clusters involves a beefing up ofbacking rolls 241 of the upper and lower clusters 16a and 17a.Similarly, in the exit stand the backing rolls 25 of the upper and lowerclusters 20 and 21 are made oversize. It will be observed that thebacking rolls 24 and 25 are those on the side of the mills respectivelyremote from the pay-off reel and the coiler. The backing rolls 24 and 25are made sufliciently larger than the other backing rolls to offset theworking rolls such an amount that the angle between the axis of aworking roll and the central backing roll is on the order of about 4.

FIG. 3 shows a further embodiment which is applicable particularly tomills according to the Sendzimir US. Pat. No. 3,318,130. These millshave the working rolls located in rotating chucks so that the workingrolls may be displaced from the centerline of the stand. Mills of thistype are also comprehended in the general turn cluster mill as usedherein although they differ specifically from those of FIGS. 1 and 2.

In this embodiment, the two intermediate stands are unmodified and aresymmetrical about the vertical.

The entrance stand 100 has its chucks 26 and 27 rotated clockwise andcounterclockwise, respectively, to displace the working rolls 28 and 29toward the pay-off reel 14. Similarly, the mill 120 has the upper andlower chucks 30 and 31 rotated counterclockwise and clockwise,respectively, to displace the work rolls 32 and 33 toward the coiler 15.The amount of displacement of the work rolls 28, 29 and 32, 33 should besuch that the angle between the axis of a working roll and the backingstructure 26 is on the order of 4 to 12.

All three embodiments of the invention result in a forced distributionwhen the mills are operating with high intra-tension such that betterrolling and more even wear of the components is achieved.

It will be understood that various modifications may be made withoutdeparting from the spirit of the invention and no limitation notspecifically set forth in the claims is intended or should be implied.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. A tandem train of multiroll mill stands for the cold rolling of a.steel strand under high intra-stand tension, including, in the ordernamed, a pay-off reel, and entrance and an exit stand at least, and acoiler, each of said entrance and exit stands being unsymmetrical withrespect to the vertical and in a mutually opposite sense, whereby tooppose said intra-stand tension.

2. A tandem train according to claim 1, wherein the unsymmetry consistsin that the backing roll structures of said entrance and exit stands aretilted away from said pay-01f reel and coiler, respectively.

3. A tandem train according to claim 2, wherein the amount of tilt isbetween 4 and 12.

4. A tandem train according to claim 1, wherein the unsymmetry consistsin that the backing structures on said entrance and exit stands are morerobust on the sides of said stands remote from said pay-01f reel andcoiler, respectively.

5. A tandem train according to claim 4, wherein the said unsymmetryresults in an angular offset of the work rolls of about 4.

6. A tandem train according to claim 1, wherein the unsymmetry consistsin that the work rolls on said entrance and exit stands are displacedfrom the stand centerlines toward said pay-off reel and coiler,respectively.

7. A tandem train according to claim 6, wherein the displacement of thework rolls results in an angular ofiset of the work rolls of between 4and 12.

References Cited UNITED STATES PATENTS 2,095,733 10/1937 Coryell 72-205X 2,237,794 4/ 1941 Sendzimir 72-205 2,303,143 11/1942 Spangler 72-205MILTON S. MEHR, Primary Examiner US. Cl. X.R. 72-234

